Control mechanism for electric switch gear



Sepi. 25, 1928.

W. ANDERSON ET AL CONTROL MECHANISM FOR ELECTRIC SWITCH GEAR 2 Sheets-Sheet 1 Filed Jan. 1926 1% w n y |l W H H 7% J HEW;

Sept; 25, 1928.

w. ANDERSON r-:r AL

CONTROL MECHANISM FOR ELECTRIC SWITCH GEAR Filed Jan. 4, 1926 2 Sheets-Sheet 2 Patented Se t; '25, 19,28;

w'mtm smensom or finneumnoiw-mmehenn mint winmsm momma, o

wsusmmgox-wms, ENGLAND, "Assmmns y'ro A. genomes & commits: mu-

f .5 nwmommesmmn A doMI'ANYoF GB-EAT BRITAIN; I

conreonfmncnntrsn .FOR Ememe swncr: GEAR.

v when ew; 1m, Seflal M 9342, in mt iiiielin tunnel-1'4, i925.

l hisiinvention shovvihgthe ih theirnormel p5 I i "efe e t wi e e rgof t e; d in, whi hr h' jvp ning-e t esw e iS e c e r,

tion shown in Figiire 1, someof the detailsibetn'Fj mechanism, whilst the closing ;of the 5 sw t h is brought about byfthemovement of a! e Various constructi n o i wi ehe nn Q hiS type have been proposed flndtheoperative connection betweenthe' handle and the tirm or-lieveroperating the switch h-as b vmn- .Flgi hM-l showing the postiionof the mesh-2b,

strolled by'trip mechanism. {In some *forms the operative conneetion hasbeen in the form sit-ion when-the switch is closed,

ing omitted to avoid confusion,

illignrefiis a viewshh'hw to that shown Figure 1 showing themomentary position of 1 e the mechanism j ust as thetoggle is breaking,

of; 1 toggle jbroken bythe r trip mechanism when some form ofcatch has? been released v I Difiielilty -1 has a beenvexpe'rienced in desi fingthe, ear sorthatthe trip meehani'smcan operate uring the whole ofthe Closing: lnovement of the switch and in many instances further difliculty'has been experienced: owing to -;powerIieceesznytooperatethe trip. I

the wear on the catchmnterielly filteringrthe The epi'imary' :obj ect of the"; present" inven e tioni istoobviate thesetdisedvaintages, 1

In switch control mechanism: according to this inventioh thlhiin'dle and the switch-op-n "eratiiig'parm or "lever :are; arranged; to turn about the "same axis, and. the i oper ti b motion between them. comprises a' toggle so f arrangedthat after beingbroken to open the switbh it is reset by: the movement of the ham-- butheforetheswitch hesgactually opened;

F gure 4 is 3V viewsimil'artot-hat showniin nism atterthesyvitch has been trippedopen but before the: trlpping mechenism has been s t- .l 1

Fignre 5, also t viewlike?thatshown in after having reset the tripping nieehenism.

geerflhohsingflC andseeured to this spindlefB ishyforked lever D :Which is; attached to, the

moving part of the switeh (not shownyliyy means (0f rop'es EZ- Q-These ropes E are et- :fdle before that member can act to elose'the,

switch; Further, the toggle after being thnfs reset can be "broken again by. thet'tripsinechii-q;

nism :itany stage in' the :closing movement of v I by a pivot'G. Theopposite end of the lever,

the switch: .As soon the! actu al' Closing 'm'ovement o-fthe hahdle and switch lever started, energy is stored, which is available I fonthebreziking of the toggle;

same power: is required 1 to ioperiite; the r trip? Whether theisivitcli beclosd'o'r in'the process of being-closed; ifl'Moreover such power is practically :nna-fiected by weer of thecatch'.

" The -ihvention 'r'ney he carried out in va rious ways but one constructionis' illustrated by Way of example-in:thefiacconipanying drawings, in which I e,

- Figure Ilsa-sectional elevationof sw tch' controlmechariism according tothe .lm'en clon 1 connected at H ,hylheans bf ,zi linkrJ tothe shorter arm K of a lever pivoted about the,

riedm a slotin the leveiiD flndmre normally in ,tension owing to the Jtendency of the switch to 1 open.

'On :11spindleFmarried hyfthe lever D is i pivoted one endrof What; maybe referred to sis the maintoggle, Which comprises two levers G- iund G whose ad scent-ends :are connected G -is pivoted-to thewlever-Dhy means of the spindle: as stated above Whilst the opposite end ofthe lever G is pivoted, at G to the shorterehdof a forked levenHEl'ot-atebly mounted itzH on the npper parUAEof; the iha-ndile A. The toggle levers-jG end G ,are provided with a stopG which preventsrelw tive m'ovement 0t thetivo leversafter they hiive'passed the deed centre positioneby more '95 .i then Ea-I predeterminedamount when: moving "towards thelei't in Figlire 11. l

The longer m-m of the forked-z lever is Y same spihdle B as the handle A. The longer ,1 armnK' :o fgthis lever; which maybe termed the catch lever, is provided with a roller K which engages with a catch L adapted to be released when it is required to trip the switch. This catch L is pivoted on a member M secured to a spindle M carried in the switchgear housing C. This member M is adapted to be moved by the action of the tappet N (Figure 2) secured to the spindle M this I tappet being actuated by electrical, mechani cal or other means. Together with the catch L the pivoted member M formsa toggle so arranged that when the member M has been moved by a small amount the catch L rotates about its pivot and falls clear of the longer arm K of the catch lever, thus releasing it. In this way the effect of wear of the catch surface on the action of the tripping mechanism is avoided.

The switch handle is made in two parts A and A connected by a pivot A and having a spring A" between them. "Theupper part A which itself turns about the spindle B to which is secured the switch-actuating lever D,'is locked when the switch is closed by a catch a which is released on the opening of the switch by a pin 13 mounted on the spindle B. To trip the switch by hand the lower part A of the handle, which may be called the handle proper, is moved in the upward direction (i. e. towards the right in Figure l), the compression of the spring A allowing relative motion between it and the locked upper part A. A projection A on the lower part A engages with the member M thereby releasing the trip I catch L and operating the mechanism.

The action of the mechanism. whether tripped mechanically or by hand is as follows Normally when the switch is closed the various parts are in the position shown in Figure 1, but on the release of thecatch L the tension in the rope E pulls on the switch actuating lever D and causes it to rotate. The toggle G G is carried'with the lever D and causes the lever H also to rotate about its the upper part A of the handle, which engages with the projection H The parts of the mechanism are now in the momentary position indicated in Figure 3 where the projection H is shownup against the stop A and the toggle is shown in the act of break ing.

As soon as the toggle has been broken the rigid connection between the switch-actuating lever D and the handle A is destroyed and the switch at once opens, the ropes E pulling the lever D and with it the main toggle G G into the position shown in Figure 4. The spindle B rotates with the lever D and as it does so the pin B releases the catch A thereby freeing the handleand enabling it to be raised to reset the trip mechanism. Figure 4 shows the final position of the various parts when the switch is open, but before the mechanism has been reset.

To reset the mechanism the handle is raised as a whole into" the position shown in Figure 5. This pulls on the main toggle G G and causes the lever H to rotate and the longer arm K of the catch lever to engage with the catch L, the main toggle G G falling into position over dead centre by gravity. Lowering the handle again closes the switch, but as the trip mechanism must of necessity be reset by first raising the handle it is always ready for operation, even during the closing of the switch. I i

It will be appreciated that the application of the toggle principle to the catch L eliminates the effect of wear ofthe catch and ensures reliable operation of the trip mechanism. Further, its application to the catch lever K .{2 and link J results in the load on the catch being kept as constant as possible throughoutthe operation of closing the switch. a

That we claim as our invention and desire to secure by Letters Patent is 1. In control mechanism for an electric switch the combination of a pivoted handle, a switch-operating arm turning about ,the same axis as the handle, a forked lever pivoted'on the upper part of the handle, a toggle normally over-set connecting the forked lever to the switch-operating arm and adapted to be broken by rotation of the forked lever about its pivot and means for preventing such rotation of the forked'lever until the mechanismis tripped. i

2. In control mechanism for an electric operating arm and adapted to be broken by rotation of the forked lever about its pivot,

means for preventing such rotation until the mechanism is tripped, means for preventing further rotation of the forked lever after the.

toggle has been broken and a locking device for the handle so constructed that the handle is capable of limited movement in order to trip the switch but cannot be moved beyond this limit until the opening of the switch has released thelocking device.

3. In control mechanism for an electric switch the combin at'ion of apivoted handle, a

: switch-operating arm turning about thesame switch the combination of a pivoted handle, -a switch-operating arm turning about the. same axis as the handle, a forked lever pivotsee aw.

adapted 'to' breakg the 'to g'glqf means for pref venting further rotationof the *fork'ed lever 'aft'ertlie toggle hasbeenbroken, a'second toggle operativelv connected to the forkedlever,

i acat'ch for h'olding the s'econd'toggle against n'ioveinent' and a lockingdevice forgthe handle so constructeiil th at the 'hairdle limited movement in orderto releas v v but cannot bemolve tlflbeyond 'tllisliinit-until th 1 etch the openingjofjgthe"switch hasieleased the locking device? r l 4. In control mechanism for an electric switch the combination of a switchgear housing, a handle pivoted thereon, a switch-operating arm turning about the same axis as the handle, a forked lever pivoted on the upper part of the handle, a toggle connecting the forked lever to the switch-operating arur, a

pro ection on the forked lever adapted to break the toggle, means for preventingfun ther rotation of the forked lever after the toggle has been broken, a catch lever also turning about the same axis asthe handle, a link forming a toggle with the catch lever p and connecting the catch lever to the forked I upper part ofthe handle, a toggle connecting a in lever, a pivoted catch engaging with the catch lever when the trip mechanism is setand a locking device for thefhandle so constructed that the handle is capable of limited movementin order to release the catch butcannot be moved beyond this limit until the opening of the switch has releasedthe locking device.

we 5. In control mechanism for an electric switch the combination of a switchgear hous a handle pivoted thereon, a switch-operating arm turning about ,the' same axis as the handle, a forked lever pivoted on the the forked lever to the switch-operatingarm, a projection on the forked lever adapted to break the toggle, means, for preventingfurther rotation of the forked lever afterthe toggle has been broken, a second toggleoperatively connected to the forked lever, a member pivoted to the switchgear housing,a catch for holding the second toggle from movement pivoted to this member andforming a third toggle therewith and means for. releasing the cat-ch. 1 7

6. In control mechanism for an electric switch the combination of a switchgear housing, a handle comprising an upper part pivoted to the housing and a lower part yieldingly connected to the upper part by means of a pivot and a spring, a swltch-operating arm turning about the same axis as the handle, a

. forked lever pivoted on the upper part of the handle, a toggle connecting the forked lever to the switch-operating arm and adapted to be broken by rotation of the forked lever about its pivot, means for preventing such capable of projection on the lower part of tlie handleff adapted to release thetrip mechanism and a[ locking device for the ham dle so constructedinforder totripthefswitch; whilst, the upper partis held stationaryuntiljth'e op'ningof the switch has released thelocking device.

l In controlmechanism for, aufel'ectric, switchthe couf 'binationof asw'itchgearhous ing, a handle comprising an u per part pivt d t0 t he-usi g a d a s i er1 a i ri 1*. ingly' co'nnectedjto the upper i part means of a pivot anda spring, aswitch opcrating arm turningabout the same axis as the handle, a forked lever pivoted on the upper part of the handle, a toggle connecting the forked lever to the switclroperating arm, a projection on the forked lever adapted to break the toggle,a stop on the upper part of the'handle adapted to prevent further rotation of the forked lever after the toggle has been broken,

forked lever, a catch for holding the second toggle against movement and a locking device for the handle so constructed that the lower part of the handle is capable of limited movement in order to release the catch, whilst the upper part is held stationary until the'opening of the switch has released the locking device. I v p 8. In control mechanismfor an electric switch the combination of a switchgear housing, ahandle comprising an upper part pivoted'to the housing and a lower part yieldingly connected to the upper part by means of a pivot and a spring, a switch-operating arm turning about thesame axis as the handle,

a forked lever pivoted on the upper part of the handle, a toggle connecting the forked lever to the switch-operating arm, a projecrotation until the imechanism, is,v tripped, a if tion on the forked lever adapted to break the i toggle, a stop on the upper part of the handle adapted to prevent further rotation of the forked lever after thetoggle has been broken,

a second toggle operatively connected'to the forked lever, a member pivoted to the switchgear housing, a catch for the second toggle pivoted 'to this member and forming "a third toggle therewith, a projection on the lower part of the handle adapted'to release the catch and a locking device for the handle so constructedth at the lower part of the handle with its projection is capable of limited movement in order to release the catch whilst the upper part is held stationary until the openingof the switch has released the locking device. H

9. In control mechanism for an electric switch the combination of a switchgear housing, a handle comprising an upper part pivoted to the housing and a lower part yieldinglyconnected to the upper part by means of a pivot and a spring, a switch-operating arm turning about the same axis as the handle. a forked lever pivoted on the upper part of the handle, a toggle connecting the forked lever to. the switch-operating arm, a projection on the forked lever adapted to break the'toggle, a stop on the upper part of the handle adapted to prevent further rotation of the forked lever after thetoggle has been broken a catch lever also turning about the same axis as the handle, a link forming a toggle with the catch lever and connecting the catch lever to the forked lever, a member pivoted on the switchgear housing, a catch pivoted on this member and forming a toggle therewith and adapted to engage the catch lever when the trip mechanism is set, a projection on the lower part of the handle adapted to release the catch and a locking device for the handle so constructed that the lower part oi the handle with its projection is capable of limited movement in order to release the catch whilst the upper part is held against movement until the opening of the switch has released the locking device.

In testimony whereof we have signed our names to this'specification.

\VILLIAM ANDERSON. I

HENRY VILLIAM OLOTHIER. 

